x86/paravirt: groundwork for 64-bit Xen support, fix

[linux-2.6] / arch / x86 / ia32 / ia32entry.S

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 8022d3c695c0dcf0d4a609387d337bf8eeaac888..24e4d4928d6534e2c390a768293a9d885624500f 100644 (file)
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -61,6 +61,19 @@
        CFI_UNDEFINED   r15
        .endm
 
+#ifdef CONFIG_PARAVIRT
+ENTRY(native_usergs_sysret32)
+       swapgs
+       sysretl
+ENDPROC(native_usergs_sysret32)
+
+ENTRY(native_irq_enable_sysexit)
+       swapgs
+       sti
+       sysexit
+ENDPROC(native_irq_enable_sysexit)
+#endif
+
 /*
  * 32bit SYSENTER instruction entry.
  *
@@ -85,14 +98,14 @@ ENTRY(ia32_sysenter_target)
        CFI_SIGNAL_FRAME
        CFI_DEF_CFA     rsp,0
        CFI_REGISTER    rsp,rbp
-       swapgs
+       SWAPGS_UNSAFE_STACK
        movq    %gs:pda_kernelstack, %rsp
        addq    $(PDA_STACKOFFSET),%rsp 
        /*
         * No need to follow this irqs on/off section: the syscall
         * disabled irqs, here we enable it straight after entry:
         */
-       sti     
+       ENABLE_INTERRUPTS(CLBR_NONE)
        movl    %ebp,%ebp               /* zero extension */
        pushq   $__USER32_DS
        CFI_ADJUST_CFA_OFFSET 8
@@ -134,7 +147,7 @@ sysenter_do_call:
        call    *ia32_sys_call_table(,%rax,8)
        movq    %rax,RAX-ARGOFFSET(%rsp)
        GET_THREAD_INFO(%r10)
-       cli
+       DISABLE_INTERRUPTS(CLBR_NONE)
        TRACE_IRQS_OFF
        testl   $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
        jnz     int_ret_from_sys_call
@@ -151,10 +164,7 @@ sysenter_do_call:
        CFI_ADJUST_CFA_OFFSET -8
        CFI_REGISTER rsp,rcx
        TRACE_IRQS_ON
-       swapgs
-       sti             /* sti only takes effect after the next instruction */
-       /* sysexit */
-       .byte   0xf, 0x35
+       ENABLE_INTERRUPTS_SYSEXIT32
 
 sysenter_tracesys:
        CFI_RESTORE_STATE
@@ -162,12 +172,14 @@ sysenter_tracesys:
        SAVE_REST
        CLEAR_RREGS
        movq    %r9,R9(%rsp)
-       movq    $-ENOSYS,RAX(%rsp)      /* really needed? */
+       movq    $-ENOSYS,RAX(%rsp)/* ptrace can change this for a bad syscall */
        movq    %rsp,%rdi        /* &pt_regs -> arg1 */
        call    syscall_trace_enter
        LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
        RESTORE_REST
        xchgl   %ebp,%r9d
+       cmpl    $(IA32_NR_syscalls-1),%eax
+       ja      int_ret_from_sys_call /* sysenter_tracesys has set RAX(%rsp) */
        jmp     sysenter_do_call
        CFI_ENDPROC
 ENDPROC(ia32_sysenter_target)
@@ -198,7 +210,7 @@ ENTRY(ia32_cstar_target)
        CFI_DEF_CFA     rsp,PDA_STACKOFFSET
        CFI_REGISTER    rip,rcx
        /*CFI_REGISTER  rflags,r11*/
-       swapgs
+       SWAPGS_UNSAFE_STACK
        movl    %esp,%r8d
        CFI_REGISTER    rsp,r8
        movq    %gs:pda_kernelstack,%rsp
@@ -206,7 +218,7 @@ ENTRY(ia32_cstar_target)
         * No need to follow this irqs on/off section: the syscall
         * disabled irqs and here we enable it straight after entry:
         */
-       sti
+       ENABLE_INTERRUPTS(CLBR_NONE)
        SAVE_ARGS 8,1,1
        movl    %eax,%eax       /* zero extension */
        movq    %rax,ORIG_RAX-ARGOFFSET(%rsp)
@@ -239,7 +251,7 @@ cstar_do_call:
        call *ia32_sys_call_table(,%rax,8)
        movq %rax,RAX-ARGOFFSET(%rsp)
        GET_THREAD_INFO(%r10)
-       cli
+       DISABLE_INTERRUPTS(CLBR_NONE)
        TRACE_IRQS_OFF
        testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
        jnz  int_ret_from_sys_call
@@ -252,8 +264,7 @@ cstar_do_call:
        TRACE_IRQS_ON
        movl RSP-ARGOFFSET(%rsp),%esp
        CFI_RESTORE rsp
-       swapgs
-       sysretl
+       USERGS_SYSRET32
        
 cstar_tracesys:        
        CFI_RESTORE_STATE
@@ -261,13 +272,15 @@ cstar_tracesys:
        SAVE_REST
        CLEAR_RREGS
        movq %r9,R9(%rsp)
-       movq $-ENOSYS,RAX(%rsp) /* really needed? */
+       movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
        movq %rsp,%rdi        /* &pt_regs -> arg1 */
        call syscall_trace_enter
        LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
        RESTORE_REST
        xchgl %ebp,%r9d
        movl RSP-ARGOFFSET(%rsp), %r8d
+       cmpl $(IA32_NR_syscalls-1),%eax
+       ja int_ret_from_sys_call /* cstar_tracesys has set RAX(%rsp) */
        jmp cstar_do_call
 END(ia32_cstar_target)
                                
@@ -306,12 +319,12 @@ ENTRY(ia32_syscall)
        /*CFI_REL_OFFSET        rflags,EFLAGS-RIP*/
        /*CFI_REL_OFFSET        cs,CS-RIP*/
        CFI_REL_OFFSET  rip,RIP-RIP
-       swapgs
+       SWAPGS
        /*
         * No need to follow this irqs on/off section: the syscall
         * disabled irqs and here we enable it straight after entry:
         */
-       sti
+       ENABLE_INTERRUPTS(CLBR_NONE)
        movl %eax,%eax
        pushq %rax
        CFI_ADJUST_CFA_OFFSET 8
@@ -325,7 +338,7 @@ ENTRY(ia32_syscall)
        jnz ia32_tracesys
 ia32_do_syscall:       
        cmpl $(IA32_NR_syscalls-1),%eax
-       ja  ia32_badsys
+       ja  int_ret_from_sys_call       /* ia32_tracesys has set RAX(%rsp) */
        IA32_ARG_FIXUP
        call *ia32_sys_call_table(,%rax,8) # xxx: rip relative
 ia32_sysret:
@@ -335,7 +348,7 @@ ia32_sysret:
 ia32_tracesys:                  
        SAVE_REST
        CLEAR_RREGS
-       movq $-ENOSYS,RAX(%rsp) /* really needed? */
+       movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
        movq %rsp,%rdi        /* &pt_regs -> arg1 */
        call syscall_trace_enter
        LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
@@ -366,13 +379,11 @@ quiet_ni_syscall:
        PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn, %rdi
        PTREGSCALL stub32_sigreturn, sys32_sigreturn, %rdi
        PTREGSCALL stub32_sigaltstack, sys32_sigaltstack, %rdx
-       PTREGSCALL stub32_sigsuspend, sys32_sigsuspend, %rcx
        PTREGSCALL stub32_execve, sys32_execve, %rcx
        PTREGSCALL stub32_fork, sys_fork, %rdi
        PTREGSCALL stub32_clone, sys32_clone, %rdx
        PTREGSCALL stub32_vfork, sys_vfork, %rdi
        PTREGSCALL stub32_iopl, sys_iopl, %rsi
-       PTREGSCALL stub32_rt_sigsuspend, sys_rt_sigsuspend, %rdx
 
 ENTRY(ia32_ptregs_common)
        popq %r11
@@ -426,7 +437,7 @@ ia32_sys_call_table:
        .quad sys_setuid16
        .quad sys_getuid16
        .quad compat_sys_stime  /* stime */             /* 25 */
-       .quad sys32_ptrace      /* ptrace */
+       .quad compat_sys_ptrace /* ptrace */
        .quad sys_alarm
        .quad sys_fstat /* (old)fstat */
        .quad sys_pause
@@ -472,7 +483,7 @@ ia32_sys_call_table:
        .quad sys_ssetmask
        .quad sys_setreuid16    /* 70 */
        .quad sys_setregid16
-       .quad stub32_sigsuspend
+       .quad sys32_sigsuspend
        .quad compat_sys_sigpending
        .quad sys_sethostname
        .quad compat_sys_setrlimit      /* 75 */
@@ -579,7 +590,7 @@ ia32_sys_call_table:
        .quad sys32_rt_sigpending
        .quad compat_sys_rt_sigtimedwait
        .quad sys32_rt_sigqueueinfo
-       .quad stub32_rt_sigsuspend
+       .quad sys_rt_sigsuspend
        .quad sys32_pread               /* 180 */
        .quad sys32_pwrite
        .quad sys_chown16